In the field of acoustics, one often desires to place an acoustic structure upon a host surface such as the floor of a host building enclosing the acoustic structure. For example, an acoustic enclosure such as a sound-proof room is placed on a floor inside a building. Such acoustic enclosures include those described in U.S. Pat. No. 6,581,724 issued to Acoustic Systems, Inc., a division of ETS Lindgren, L. P., the assignee of the present invention.
In many applications one desires to prevent sound waves from being transmitted between the host surface and the acoustic enclosure. For this reason, the acoustic structure is mounted upon the surface using a sound absorbing mechanism. An expanded view of an assembly for mounting an acoustic enclosure upon a floor of a host building is shown in FIG. 1. Resting upon the host floor 100 are isolators 120 and 130. Each isolator assembly is formed from an upper conventional C-channel 150 and a lower conventional C-channel 160. Between these two channels is a sound absorber 140, which absorbs vibrations between the floor 100 and upper channel 150. Absorber 140 substantially prevents transmission of sound between host floor 100 and an acoustic floor 1000. Absorber 140 may be made of elastomer or other known material. Resting upon isolators 120 and 130 is acoustic floor 1000 formed by a lower floor plate 170 and an upper floor plate 180 supported by vertical supports 190. In the region between the upper and lower plates is placed sound absorbing material to form the acoustic floor.
Acoustic floor 1000 is of a height X and isolators 120 and 130 are of a height Y. The total height of the step from the host floor 100 to the top of the acoustic floor 1000 is X+Y. This reduces the space between the acoustic floor and the interior ceiling of the acoustic enclosure, the height of the interior ceiling being limited by the height of the ceiling of the host room within which the acoustic enclosure is located.
Further, when a ramp is required, for example, to comply with the Americans with Disabilities Act, or to roll equipment into and out of the acoustic enclosure, the height of the step, X+Y, dictates the length of the ramp. For example, the length of the ramp may be required to be not less than X+Y inches times one foot per inch. Thus, if the height of the step is 7.5 inches, the ramp must be 7.5 feet long!
Moreover, in some instances, there must be no step at all. That is, the floor of the acoustic enclosure must be level with a host floor, as indicated by the raised floor section 111. This results in considerable difficulty installing the acoustic floor because the acoustic floor must be leveled. If not level, the acoustic floor must be removed so that shims can be placed under the isolators to level the floor. As can be imagined, this can be a laborious, time-consuming task.
For at least these reasons, there is a need for a method for mounting an acoustic structure upon a host surface that reduces the step height of the floor of the acoustic structure and enables easy leveling of the floor of the structure.